The present invention relates to valves in general, and more particularly to improvements in valves which can be utilized in syphons or the like. Still more particularly, the invention relates to improvements in valves which can be utilized for dispensing confined pressurized flowable media, such as cream, and for ensuring that the pressure of the confined media does not rise beyond a permissible value.
It is already known to install a dispensing valve in the cover or cap of a syphon which contains a supply of pressurized cream or another flowable medium and to provide the cap with a safety valve which opens as soon as the pressure in the interior of the syphon exceeds a preselected threshold value. The dispensing valve can be actuated by a so-called metering pin which can be tilted by the operator and is normally confined in a tubular body, or by a spring-biased lever which is pivotally secured to the cover. The utilization of two discrete valves, namely a dispensing valve and a safety valve, often presents problems because such valves occupy too much space in and/or on the cover. Moreover, two discrete valves contribute to the cost of the device wherein the valves are installed, and the manipulation of the dispensing valve can interfere with the operation of the safety valve.
Attempts to overcome the aforediscussed drawbacks of conventional two-piece dispensing valve-safety valve combinations include the provision of an assembly including a dispensing valve with a built-in safety valve. Heretofore known valve assemblies of such type are not entirely satisfactory, not only because they are complex, overly sensitive, bulky and expensive but also because they can be used only if the dispensing valve is to be actuated by a lever. In all devices wherein the dispensing valve is actuated by a pivotable or similarly movable metering pin, the safety valve invariably constitutes a discrete part which must be installed independently of and occupies space in addition to that occupied by the dispensing valve. Moreover, presently known assemblies wherein the dispensing and safety valves constitute a self-sustaining unit cannot be installed in existing syphons or like devices in lieu of a pair of discrete (dispensing and safety) valves.